bnxt_en: avoid link reset if speed is not changed

PORT_PHY_CONFIG is always sent with REQ_FLAGS_RESET_PHY set. This flag
must be set in order for the firmware to institute the requested PHY
change immediately, but it results in a link flap. This is unnecessary
and results in an improved user experience if the PHY reconfiguration
is avoided when the user requested speed does not constitute a change.

Signed-off-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index 2cb2495..4fdb672 100644 (file)
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -1736,6 +1736,11 @@ static int bnxt_force_link_speed(struct net_device *dev, u32 ethtool_speed)
                return -EINVAL;
        }
 
+       if (link_info->req_link_speed == fw_speed &&
+           link_info->req_signal_mode == sig_mode &&
+           link_info->autoneg == 0)
+               return -EALREADY;
+
        link_info->req_link_speed = fw_speed;
        link_info->req_signal_mode = sig_mode;
        link_info->req_duplex = BNXT_LINK_DUPLEX_FULL;
@@ -1816,8 +1821,11 @@ static int bnxt_set_link_ksettings(struct net_device *dev,
                }
                speed = base->speed;
                rc = bnxt_force_link_speed(dev, speed);
-               if (rc)
+               if (rc) {
+                       if (rc == -EALREADY)
+                               rc = 0;
                        goto set_setting_exit;
+               }
        }
 
        if (netif_running(dev))